.main-bg{
  position: relative;
  background-color:#eee;
  border:1px solid #999;
}
aside , article{
  background-color:#fff;
}
.left{
  position: absolute;
  width: 160px;
}

.main{
  min-height: 400px;
  margin-left: 220px;
  margin-right: 140px;
}
.right{
  position: absolute;
  right: 20px;
  width: 80px;
}

.logo{
  width: 80px;
  height:80px;
}